What Age Difference Between A Man And A Woman Is Preferable For Marriage? Research And Study Reveals;

Age disparity in sexual relationships is the difference in ages of individuals in sexual relationships. Concepts of these relationships, including what defines an age disparity, have developed over time and vary among societies. 

Differences in age preferences for mates can stem from evolutionary mating strategies and age preferences in sexual partners may vary cross culturally. There are also social theories for age differences in relationships as well as suggested reasons for 'alternative' age-hypogamous relationships. Age-disparity relationships have been documented for most of recorded history and have been regarded with a wide range of attitudes dependent on sociocultural norms and legal systems.

Male preference for younger females

A renounced scientist David Buss attributed the male preference for younger females to certain youthful cues. In females, relative youth and physical attractiveness (which males valued more compared to females) demonstrated cues for fertility and high reproductive capacity. Buss stated the specific age preference of around 25 years implied that fertility was a stronger ultimate cause of mate preference than reproductive value as data suggested that fertility peaks in females around mid-twenties.

From a life history theory perspective, females that display these cues are judged to be more capable of reproductive investment. This notion of age preference due to peak fertility is supported by Kenrick, Keefe, Gabrielidis, and Cornelius's study, which found that although teenage males would accept a mate slightly younger than themselves, there was a wider range of preference for ages above their own. Teenage males also report that their ideal mates would be several years older than themselves.

Buss and Schmitt stress that although long term mating relationships are common for humans, there are both short term and long term mating relationships. Buss and Schmitt provided a Sexual Strategies Theory that describes the two sexes as having evolved distinct psychological mechanisms that underlie the strategies for short and long term mating. This theory is directly relevant and compatible with those two already mentioned, Life History and Parental Investment.

Males tend to appear oriented towards short term mating (greater desire for short term mates than women, prefer larger number of sexual partners and take less time to consent to sexual intercourse) and this appears to solve a number of adaptive problems including using fewer resources to access a mate. Although there are a number of reproductive advantages to short term mating, males still pursue long term mates, and this is due to the possibility of monopolising a female's lifetime reproductive resources. Consistent with findings, for both short term and long term mates, males prefer younger females (reproductively valuable).

Female preference for older males

As they are the higher investing sex, females tend to be slightly more demanding when picking a mate (as predicted by parental investment theory). They also tend to have a more difficult task of evaluating a male's reproductive value accurately based on physical appearance as age tends to have fewer constraints on a male's reproductive resources. Buss attributed the older age preference to older males displaying characteristics of high providing-capacity such as status and resources.

In terms of short term and long term mating, females tend be oriented towards long term mating due to the costs incurred from short term mating. Although some of these costs will be the same for males and females (risk of STIs and impairing long term mate value), the costs for women will be more severe due to paternity uncertainty (cues of multiple mates will be disfavoured by males).

In contrast to above, in short term mating, females will tend to favour males that demonstrate physical attractiveness as this displays cues of 'good genes'. Cues of good genes tend to be typically associated with older male such as facial masculinity and cheek-bone prominence. Buss and Schmitt found similar female preferences for long term mating which supports the notion that for long term relationships females prefer cues of high resource capacity, one of which is age.

Regional singulate mean age of marriage (SMAM) difference between males and females
Region	SMAM difference
Eastern Africa	4.3
Middle Africa	6.0
Northern Africa	4.5
Western Africa	6.6
Eastern Asia	2.4
South-Central Asia	3.7
South-Eastern Asia	2.4
Western Asia	3.5
Eastern Europe	3.1
Northern Europe	2.3
Southern Europe	3.3
Western Europe	2.7
Caribbean	2.9
Central America	2.5
South America	2.9
Northern America	2.3
Australia/New Zealand	2.2